The first four ingredients are soluble and are extracted as the gum is chewed. The gum base moves intact through the normal digestive process in a few days, much as roughage does.

Makers do not advocate swallowing, but it would not hurt more than eating a big bag of popcorn.

Some manufacturers use various forms of latex as a base, and it passes safely through the digestive system, much as a rubber band would.

Like toothpaste, chewing gum is defined as a food for the purpose of Food and Drug Administration regulation.

The original formulations of many gums might predate F.D.A. regulation, but as each new ingredient, like a modern synthetic gum base, is added, the regulators take into consideration that it could be swallowed.

The amount that would normally be swallowed must be safe for people.

Medical authorities say that small children should not be allowed to chew gum because they might choke on it.